A054163 Number of positive integers <= 2^n of form 3 x^2 + 6 y^2.

0, 0, 1, 2, 4, 7, 13, 23, 43, 78, 144, 269, 502, 945, 1794, 3414, 6537, 12559, 24195, 46751, 90539, 175693, 341530, 664965, 1296520, 2531118, 4946995, 9678777, 18954593, 37152384, 72879304, 143067454, 281043183, 552433040, 1086529470